(a) Field of the Invention
The present invention relates to an apparatus and method of controlling a vehicle including a drive motor, and more particularly, to an apparatus and method of controlling a vehicle which is linearly decreased during shifting.
(b) Description of the Related Art
An environmentally-friendly technology of a vehicle is a core technology which controls survival of a future automobile industry, and advanced vehicle manufacturers have focused attention on the development of an environmentally-friendly vehicle to achieve environmental and fuel efficiency regulations. Therefore, vehicle manufacturers have developed an electric vehicle (EV), a hybrid electric vehicle (HEV), a fuel cell electric vehicle (FCEV), and the like, as future vehicle technologies.
The vehicle manufacturers consider the hybrid electric vehicle as an alternative vehicle for solving realistic problems such as satisfaction of exhaust gas regulations and enhancement of fuel efficiency performance, and have conducted research and development to commercialize the hybrid electric vehicle. In general, the electric vehicle, the hybrid vehicle, and the fuel cell vehicle are driven by a drive motor that obtains torque through electrical energy. Particularly, the hybrid vehicle is a vehicle that uses two or more power sources, and an engine and a drive motor are used as the power sources of the hybrid vehicle. The vehicle having the drive motor operates the drive motor as a generator while driving by braking or inertia to recover braking or inertia energy, thereby charging the battery. In particular, the torque of the drive motor has a negative value and provides a braking force operated in a direction opposite to the driving direction of the vehicle.
The vehicle having the drive motor is then required to down-shift while driving with the braking or inertia. While performing the down-shift, a speed (i.e., a speed of the drive motor) of the input shaft of the transmission is increased to a speed that corresponds to a target shift state. According to the conventional shift control method, to improve the shift feel, an absolute value of the torque of the drive motor is adjusted using a torque intervention method, and engagement and disengagement of an off-going element and an on-coming element of the transmission is performed. However, according to the convention art, since a toque variation of the drive motor cannot be accurately predicted during shifting, the vehicle is not linearly decelerated and thus a driver feels a sense of difference.
The above information disclosed in this section is merely for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.